WHERE [кому] not in (10,20)

declare @__TEMP table(ID int identity(1, 1) primary key, IDProduct int, StoreFrom int, StoreTo int)

insert @__TEMP(IDProduct, StoreFrom, StoreTo)
          select 1, 12, 10
union all select 1, 10, 20
union all select 1, 20, 101
union all select 2, 12, 10
union all select 2, 10, 114
union all select 3, 12, 10
union all select 3, 10, NULL

--select * from @__TEMP

select t.IDProduct, t1.StoreFrom, t2.StoreTo
from (select IDProduct, min(ID) ID_min, max(ID) ID_max from @__TEMP group by IDProduct) t
join @__TEMP t1 on t1.IDProduct = t.IDProduct and t1.ID = t.ID_min
join @__TEMP t2 on t2.IDProduct = t.IDProduct and t2.ID = t.ID_max
where
		t1.StoreFrom not in (10, 20)
or		t1.StoreFrom not in (10, 20)

--если условия в реальности хитрее чем в примере то можни использовать cross apply
select t.IDProduct, t1.StoreFrom, t2.StoreTo
from (select distinct IDProduct from @__TEMP) t
cross apply(select top 1 t1.StoreFrom
			from @__TEMP t1
			where
					t1.IDProduct = t.IDProduct
			order by t1.ID asc) t1
cross apply(select top 1 t2.StoreTo
			from @__TEMP t2
			where
					t2.IDProduct = t.IDProduct
			order by t2.ID desc) t2

where
		t1.StoreFrom not in (10, 20)
or		t1.StoreFrom not in (10, 20)

declare @tbl table
(
	товар int,
	отКого int,
	кому int
)
insert @tbl values
 (1, 12, 10	 )
,(1, 10, 20	 )
,(1, 20, 101 )
,(2, 12, 10	 )
,(2, 10, 114 )
,(3, 12, 10	 )
,(3, 10, NULL)
,(4, 15, 16)
,(4, 16, 15)

declare @tbl table
(
	товар int,
	отКого int,
	кому int,
	дата datetime
)
insert @tbl values
 (1, 12, 10		,'2013-01-01')
,(1, 10, 20		,'2013-01-02')
,(1, 20, 101	,'2013-01-03')
,(2, 12, 10		,'2013-01-04')
,(2, 10, 114	,'2013-01-05')
,(3, 12, 10		,'2013-01-06')
,(3, 10, NULL	,'2013-01-07')
,(4, 15, 16		,'2013-01-08')
,(4, 16, 15		,'2013-01-09')
;
with c as
(
select *
	,row_number() over (partition by товар order by дата asc) as номер1
	,row_number() over (partition by товар order by дата desc) as номер2
from @tbl
)
select
	c1.товар,
	c1.отКого,
	c2.кому
from c as c1 join c c2
	on c1.товар = c2.товар
	and c1.номер1=1
	and c2.номер2=1

declare @__TEMP table(ID int identity(1, 1) primary key, IDProduct int, StoreFrom int, StoreTo int)

insert @__TEMP(IDProduct, StoreFrom, StoreTo)
          select 1,  12, 10
union all select 1,  10, 20
union all select 1,  20, 101
union all select 1, 101, 102
union all select 1, 102, 103
union all select 1, 103, 101
union all select 1, 101,  10
union all select 1,  10, NULL

union all select 2, 12, 10
union all select 2, 10, 114

union all select 3, 12, 10
union all select 3, 10, NULL

select
t3.IDProduct, 
row_number() over(partition by t3.IDProduct order by t3.NNX asc) NNX_2, 
NULLIF(t3.Stores, -1) StoresFrom,  
NULLIF(t3.StoresNext, -1)StoresTo
from   (select
	   t.IDProduct, 
	   t2.Stores,
	   row_number() over(partition by t.IDProduct order by t.ID asc, t2.NN asc) NNX,
	   LEAD(t2.Stores, 1) over(partition by t.IDProduct order by t.ID asc, t2.NN asc) StoresNext
	   from @__TEMP t
	   --- выстраиваем их в цепочку
	   cross apply(select 1 NN, IsNULL(t.StoreFrom, -1) Stores where IsNULL(t.StoreFrom, 0) not in (10, 20)
	   		    union all
			    select 2 NN, ISNULL(t.StoreTo,   -1)        where IsNULL(t.StoreTo,   0) not in (10, 20) /**/ ) t2 /**/ ) t3
where
		t3.Stores != t3.StoresNext -- убираем дубли
order by  t3.IDProduct, NNX_2

WITH
Res (IDProduct, StoreFrom, StoreTo, _Level)
AS (SELECT t.IDProduct, t.StoreFrom, t.StoreTo, 1 _Level FROM TestTable t
	WHERE NOT EXISTS (SELECT 1 FROM TestTable WHERE IDProduct = t.IDProduct AND StoreTo = t.StoreFrom)
	UNION ALL
	SELECT t.IDProduct, t.StoreFrom, t.StoreTo, r._Level + 1 FROM Res r 
	JOIN TestTable t ON t.IDProduct = r.IDProduct AND t.StoreFrom = r.StoreTo
   )
SELECT r.IDProduct, r.StoreFrom, r1.StoreTo FROM Res r
JOIN Res r1 ON r1.IDProduct = r.IDProduct AND r1._Level = (SELECT MAX(_Level) FROM Res WHERE IDProduct = r.IDProduct)
WHERE r._Level = 1
ORDER BY r.IDProduct;